What must be the beta of a portfolio with E(rP) = 31.00%. if rf = 4% and E(rM) = 19%?. The market price of a security is $74. Its expected rate of return is 13%. The risk-free rate is 7%, and the market risk premium is 9%. What will the market price of the security be if its beta doubles (and all other variables remain unchanged)? Assume the stock is expected to pay a constant dividend in perpetuity